[cautious_int]

Why not put it into a Faraday cage?

[pgeorgi]

Like everything sold on https://shop.digitalcourage.de/thema/stoprfid/ (the 'support shop' of an organization doing privacy advocacy)

[richmarr]

This is actually a good point.

Rather than putting your ID card or passport in a microwave (and breaking the law), you could just use an RFID-blocking wallet or passport holder.

[TheLoneWolfling]

Because you still, presumably, need to take it out of the Faraday cage to use it.